219 research outputs found

    Expression of genes encoding extracellular matrix macromolecules and metalloproteinases in avian tibial dyschondroplasia

    Get PDF
    Avian tibial dyschondroplasia (TD) is a skeletal disease characterized by disruption of endochondral bone formation. The aim of this study was to determine the expression of extracellular matrix (ECM) macromolecules and ECM-degrading enzymes [matrix metalloproteinases (MMPs)] in the growth plates of normal and TD-affected 3-week-old broiler chicks (Cobb strain). Protein levels were analyzed by immunoblotting and gelatin zymography and gene expression by polymerase chain reaction. Expression of genes encoding the ECM macromolecules (collagen types II, IX, X and XI; and aggrecan) was not altered in dyschondroplasia; however, there was down-regulation of genes encoding MMP-9, MMP-13, MMP-10 and MMP-11 in addition to reduced amounts of MMP-2 and MMP-13 proteins. In contrast, there was up-regulation of genes encoding MMP-7 and the vascular endothelial growth factor. These findings suggest that the accumulation of cartilage associated with the disease may be the result of decreased proteolysis due to the down-regulation of MMPs and not to an increased production of ECM macromolecules

    Pterygoplichthys undecimalis (Siluriformes: Loricariidae): una especie trasplantada en la cuenca del río Patía, vertiente Pacífico, Colombia

    Get PDF
    In Colombia, records of fishes of the family Loricariidae transplanted in different freshwater systems are unknown. In this work, the history of the transplant of the loricariid Pterygoplichthys undecimalis, that is naturally distributed in several rivers different rivers that drain to the Caribbean of Colombia, into the upper Patía River Basin, that drains to the Pacific is described. Our observations show that the species has been successfully established in different tributaries of the Patía River, with the first records during 2006 and the most recent records in 2016.En Colombia se desconocen registros del trasplante de peces de la familia Loricariidae en los diferentessistemas dulceacuícolas. El presente trabajo describe la historia del trasplante en la cuenca alta del río Patíaque drena al Pacífico, del loricárido Pterygoplichthys undecimalis que se distribuye naturalmente en diferentesríos que drenan a la vertiente del Caribe de Colombia. Las observaciones realizadas indican que la especie seha establecido exitosamente en diferentes afluentes del río Patía, con los primeros registros en el año 2006 ylos más recientes en el 2016

    Estudo sobre os embargos de nulidade e infringentes do julgado previstos no código de processo civil

    Get PDF
    Tese (Catedra) - Faculdade de Direito da Universidade do ParanaInclui referências e índic

    Detection of genetic incompatibilities in non-model systems using simple genetic markers: hybrid breakdown in the haplodiploid spider mite Tetranychus evansi

    Get PDF
    When two related species interbreed, their hybrid offspring frequently suffer from reduced fitness. The genetics of hybrid incompatibility are described by the Bateson–Dobzhansky–Muller (BDM) model, where fitness is reduced by epistatic interactions between alleles of heterospecific origin. Unfortunately, most empirical evidence for the BDM model comes from a few well-studied model organisms, restricting our genetic understanding of hybrid incompatibilities to limited taxa. These systems are predominantly diploid and incompatibility is often complete, which complicates the detection of recessive allelic interactions and excludes the possibility to study viable or intermediate stages. Here, we advocate research into non-model organisms with haploid or haplodiploid reproductive systems and incomplete hybrid incompatibility because (1) dominance is absent in haploids and (2) incomplete incompatibility allows comparing affected with unaffected individuals. We describe a novel two-locus statistic specifying the frequency of individuals for which two alleles co-occur. This approach to studying BDM incompatibilities requires genotypic characterization of hybrid individuals, but not genetic mapping or genome sequencing. To illustrate our approach, we investigated genetic causes for hybrid incompatibility between differentiated lineages of the haplodiploid spider mite Tetranychus evansi, and show that strong, but incomplete, hybrid breakdown occurs. In addition, by comparing the genotypes of viable hybrid males and inviable hybrid male eggs for eight microsatellite loci, we show that nuclear and cytonuclear BDM interactions constitute the basis of hybrid incompatibility in this species. Our approach opens up possibilities to study BDM interactions in non-model taxa, and may give further insight into the genetic mechanisms behind hybrid incompatibility

    Van de grond : verkenning mogelijkheden voor het inzetten van publieke grond voor maatschappelijke doelen in Eemland

    Get PDF
    Eemland is één van de beste weidevogelgebieden van Nederland. Veel boeren doen al aan agrarisch natuurbeheer, maar de groei is eruit. Agrarische natuur- en landschapsvereniging Ark & Eemlandschap zou graag meer in handen hebben dan de subsidieregeling SNL om boeren te stimuleren om mee te doen. Zij ziet in grondgebruiksrecht een potentiële extra beloning, juist omdat grond schaars is. Hoge grondprijzen en een lage grondmobiliteit zijn typische problemen van stadsrandgebieden zoals Eemland. Ark & Eemlandschap zou grond in bezit bij overheden en maatschappelijke organisaties graag inzetten om extra groenblauwe diensten te stimuleren. Voor het verdelen van de publieke grond kan worden gedacht aan een grondbank als organisatievorm. Ark & Eemlandschap wil namelijk met de grondbank publieke grond in pacht uitgeven, in ruil voor extra agrarisch natuurbeheer (of klompenpaden) op grond die de boer al in gebruik of in bezit heeft. Op deze manier wil Ark & Eemlandschap boeren verleiden om bijvoorbeeld op voor de weidevogel gunstige plekken agrarisch natuurbeheer te gaan doen

    Transcriptome analysis reveals the high ribosomal inhibitory action of 1,4-naphthoquinone on Meloidogyne luci infective second-stage juveniles

    Get PDF
    The root-knot nematode (RKN) Meloidogyne luci presents a threat to the production of several important crops. This nematode species was added to the European Plant Protection Organization Alert list in 2017. The scarce availability of efficient nematicides to control RKN and the phasing out of nematicides from the market have intensified the search for alternatives, such as phytochemicals with bionematicidal properties. The nematicidal activity of 1,4-naphthoquinone (1,4-NTQ) against M. luci has been demonstrated; however, knowledge of the potential mode(s) of action of this compound is still scarce. In this study, the transcriptome profile of M. luci second-stage juveniles (J2), the infective stage, in response to 1,4-NTQ exposure was determined by RNA-seq to identify genes and pathways that might be involved in 1,4-NTQ’s mode(s) of action. Control treatments, consisting of nematodes exposed to Tween® 80 (1,4-NTQ solvent) and to water, were included in the analysis. A large set of differentially expressed genes (DEGs) was found among the three tested conditions, and a high number of downregulated genes were found between 1,4-NTQ treatment and water control, reflecting the inhibitory effect of this compound on M. luci, with a great impact on processes related to translation (ribosome pathway). Several other nematode gene networks and metabolic pathways affected by 1,4-NTQ were also identified, clarifying the possible mode of action of this promising bionematicide

    Incomplete Punishment Networks in Public Goods Games: Experimental Evidence

    Get PDF
    Abundant evidence suggests that high levels of contributions to public goods can be sustained through self-governed monitoring and sanctioning. This experimental study investigates the effectiveness of decentralized sanctioning institutions in alternative punishment networks. Our results show that the structure of punishment network significantly affects allocations to the public good. In addition, we observe that network configurations are more important than punishment capacities for the levels of public good provision, imposed sanctions and economic efficiency. Lastly, we show that targeted revenge is a major driver of anti-social punishment

    Implementation of the Product Environmental Footprint Category Rules for dairy products: An approach to assess nitrogen emissions in a mass balanced dairy farm system

    Get PDF
    European Union’s Horizon 2020 research and innovation programme and Agency for Business Competitiveness of the Government of Cataloni

    Cooperation and Contagion in Web-Based, Networked Public Goods Experiments

    Get PDF
    A longstanding idea in the literature on human cooperation is that cooperation should be reinforced when conditional cooperators are more likely to interact. In the context of social networks, this idea implies that cooperation should fare better in highly clustered networks such as cliques than in networks with low clustering such as random networks. To test this hypothesis, we conducted a series of web-based experiments, in which 24 individuals played a local public goods game arranged on one of five network topologies that varied between disconnected cliques and a random regular graph. In contrast with previous theoretical work, we found that network topology had no significant effect on average contributions. This result implies either that individuals are not conditional cooperators, or else that cooperation does not benefit from positive reinforcement between connected neighbors. We then tested both of these possibilities in two subsequent series of experiments in which artificial seed players were introduced, making either full or zero contributions. First, we found that although players did generally behave like conditional cooperators, they were as likely to decrease their contributions in response to low contributing neighbors as they were to increase their contributions in response to high contributing neighbors. Second, we found that positive effects of cooperation were contagious only to direct neighbors in the network. In total we report on 113 human subjects experiments, highlighting the speed, flexibility, and cost-effectiveness of web-based experiments over those conducted in physical labs
    corecore